The primary goal of the Data Coordination and Statistical Core (DCSC) is to provide a coherent and consistent approach to field procedures and data management, with sharing of statistical methodology across all Projects and Cores. By standardizing protocols and centralizing data management, we not only insure data integrity and realize individual study goals, but we also facilitate inter-project scientific collaboration amongst Project and Core investigators. The Data Management and Coordination Component will provide centralized expertise and resources for management, quality control, quality assurance, storage and access to Project and Core data. The DCSC will provide centralized data tracking, processing, quality assurance procedures and documentation management. Finally the DCSC will ensure that data are accessible to Program investigators in a timely fashion, through a centralized, shared-access study database with regular back-up and archiving. The Environmental Statistics Component will serve as a centralized resource for understanding and implementing the statistical methods needed for the projects, including analysis of panel data and case-crossover studies, as well as expertise in nonparametric smoothing, including within the context of mixed models, repeated measures, structural equation models, and risk assessment.